Increasing voluntary feed intake by the chick: Experiments on managing eating behavior.

摘要

Palatability of diets based on several grains was evaluated by chicks. Then an attempt was made to increase feed intake by sequencing discriminatable diets.;Feeder type influenced neither feed intake nor weight gain, except intake tended to be lower with "short" feeders than "long" or "round", resulting in higher feed-conversion efficiency with "short". Feeding method affected intake, gain, and efficiency; restricted access (6 h/d) decreased all three. Freshness of feed did not influence gain or efficiency, but stale feed tended to reduce intake.;Preferences for bitter materials (sucrose octa-acetate and quinine sulfate) at different dietary concentrations were evaluated. Chicks preferred the bitter-free diet over bitter diets. But with no choice they habituated to bitter diets. Intake and gain were lower on bitter diets, although efficiency did not change.;Chick preferences for diets based on barley, buckwheat, corn, millet, milo, rye, triticale, and wheat, respectively, were evaluated. Diets were offered ad libitum in both choice (cafeteria of three or four) and no-choice situations. With choice, chicks preferred specific diets. Barley-, millet-, and triticale-based diets were most palatable. With no choice, however, diets did not differ for intake, gain, or efficiency. Cafeteria offering increased intake and gain, but efficiency decreased.;When diets were changed one time per day (1x/d), intake did not differ from that when changed 2x/d, but gain and efficiency were higher for 1x/d.;Fixed versus random order of diet changing had no effect, but intake tended to be influenced by particular sets of diets. More of set ABCD (barley-, wheat-, millet-, triticale-based diets) was consumed than of ABCH (H = buckwheat-), but neither differed from ABGH (G = corn-). Gain on ABGH was lower than on ABCD, but tended to be lower than on ABCH. Diets in set ABCH were used more efficiently than those in either ABCD or ABGH.;Intake was decreased by changing diets in a fixed sequence (here, BWMT = barley-, wheat-, millet-, triticale-) 4x/d in contrast to 0x/d or 2x/d. Chicks consumed the millet-based diet the most, the triticale- the least. Preference for or aversion to a diet became more marked as changing frequency increased. Changing diets 4x/d reduced gain compared to 1x/d changing or 0x/d barley-based diet, but not to 0x/d wheat-, millet-, or triticale- or 2x/d or 6x/d changing.;The 0x/d millet-based diet was used more efficiently than the 0x/d triticale- or 1x/d changing. The 0x/d barley- and 6x/d changing also were associated with higher efficiency than was 1x/d changing. Efficiency was increased by increasing frequency of diet changing.